In current semiconductor industry, integrated circuit (IC) products mainly include three types of devices: logic devices, memory devices, and analog circuits. Among these three types of devices, memory devices account for a large proportion of the IC products. With the development of semiconductor technology, in order to expand the application range of memory devices, it is necessary to simultaneously form memory devices together with other types of devices on a same chip to form an embedded semiconductor memory device. For example, to embed a memory device in a central processing unit (CPU), the memory device may need to be compatible with the embedded CPU platform, and the original specifications and the corresponding electrical performance of the memory device may need to be retained.
Usually, the memory device may need to be compatible with the embedded standard logic device. For an embedded semiconductor device, the device may often include a logic region and a storage region. The logic region may usually include a plurality of logic devices, the storage region may include a plurality of memory devices. With the development of memory technology, various types of semiconductor memories such as static random access memories (SRAMs), dynamic random access memories (DRAMs), erasable programmable read-only memories (EEPROMs), flash memories, etc. have emerged. Among the various types of semiconductor memories, SRAM devices demonstrate a number of advantages such as low energy-consumption, relatively-fast operation speed, etc. Therefore, SRAM devices and the corresponding fabrication methods have attracted more and more attention.
However, the electrical performance of conventional SRAM devices may still need to be improved. The disclosed SRAM devices and fabrication methods thereof are directed to solve one or more problems set forth above and other problems in the art.